\tracingonline=2
\tracingcommands=2
\tracingmacros=2
\tracingrestores=2

\catcode`{=1
\catcode`}=2

\count`\string a=10
\showthe\count`a

\newlinechar=`@
\message{~ \string abc@}
\message{~ \string 123@}
\message{~ \string\count1@}

\message{~ \string\relax @}
\message{~ \string\end @}

% double expansion
\message{~ \string\string125@}
\message{~ \string\string\string\relax @}

\message{~ \string a \string b \string c @}

\end
